ataxic Yorkie

Re: ataxic Yorkie

ilanit — Wed, 22 Aug 2012 16:37:29 GMT

After four days of steroids the dog seems back to normal! Hope it won't relapse; will follow your recommended schedule, while awaiting BA results. Thanks again.

Re: ataxic Yorkie

ilanit — Mon, 20 Aug 2012 16:57:35 GMT

Thank you!

Re: ataxic Yorkie

Mark Lowrie — Mon, 20 Aug 2012 16:34:57 GMT

Dorsal deviation of the neck is not very specific. We tend to see it with decerebrate and decerebellate posture. The former occurs without mentation changes and the latter is associated with mentation changes. You would usually expect some forelimb hyperextension with these postures and they can be intermittent as you describe. Therefore if I were to guess I would say this dog has an intra-cranial problem based on the presence of dorsal deviation of the neck.

Schiff-Scherrington posture can give the appearance of dorsal deviation of the neck but this is following severe TL spinal cord lesions which doesn’t fit with the signs in this case.

The signs appear waxing and waning from your original description as the dog seems slightly improved in the video compared to your first exam. This would fit quite nicely with metabolic brain disease (e.g. PSS), even if the dog is getting worse with time. I tend to always test for PSS in a YRT with neuro signs regardless as I am always surprised by how they can present – either blood ammonia or Bile acid stim is sufficient.

Re: ataxic Yorkie

ilanit — Mon, 20 Aug 2012 15:54:03 GMT

Thanks for your replies!!

With regards to Ehrlichia. We are in endemic area over here (Malta). Seeing Ehrlichia on a daily basis here. I don't think this dog has Ehrlichiosis though. The test was a bit dubious (very slight positive line on test), but of course it could be acute ehrlichiosis. However there are no other signs indicating Ehrlichia. Hematology normal, no fever, no enlarged lymphnodes. That aside my colleague started Doxycyclin a week ago with no response. I am still continuing it 'just in case' but not suspecting it will do.

Yesterday I gave a steroid injection and the owner said he was much better after that but this morning got a bit worse again (however he was still improved compared to when I saw him the day before).

Awareness is normal. Dog just seems stressed and panting a lot, but they say this settled after steroid. Menace normal. proprioception ok. Did not try hopping to be honest.

What does the dorsal deviation on the neck (which is not so pronounced on the video, but was worse) say about neuropathological location? Brain stem? Upper spinal cord?

Wouldn't HE present more episodic?

Thanks again!

Re: ataxic Yorkie

James Laidlaw — Mon, 20 Aug 2012 11:44:41 GMT

Thanks Mark.

Re: ataxic Yorkie

Mark Lowrie — Mon, 20 Aug 2012 11:05:36 GMT

[quote user="James Laidlaw"]

Is the Ehrlichia test positive something to consider? Could fit the symptoms seen:

(Stolen from IVIS.org)

A wide variety of clinical signs, from mild to severe,

have been reported in the acute stage of E. canis infections.

Some dogs present with nonspecific signs such as fever,

lethargy, anorexia, lymphadenopathy, splenomegaly and

weight loss. Vomiting, diarrhea, lameness, edema in the hind

legs, coughing, dyspnea, and a serous to purulent oculonasal

discharge may also be seen. Symptoms of bleeding disorders

including anemia, mild epistaxis, petechiae and ecchymoses

have been reported. Ocular signs can include anterior uveitis,

corneal opacity, hyphema and tortuous retinal vessels. Focal

chorioretinal lesions, consisting of central pigmented spots

with surrounding areas of hyperreflectivity, may be seen.

Subretinal hemorrhages can cause retinal detachment and

blindness. The acute phase typically lasts for 1 to 4 weeks,

and the symptoms usually resolve spontaneously.

Some dogs that recover clinically from the acute phase

remain subclinically infected for months or years. During

the subclinical stage, an infected dog can clear the parasite,

remain infected but asymptomatic, or develop chronic

disease. There may also be progressive deterioration in the

hematologic values during this stage. The conditions leading

to the development of the chronic phase are unknown.

In the chronic phase, common symptoms include chronic

weight loss, weakness, depression, fever, anorexia, and

edema of the limbs, tail and scrotum. Bleeding disorders

occur frequently, and may result in pale mucous membranes,

petechiae, ecchymoses, epistaxis, hematuria or melena. Pancytopenia

can occur, and may lead to secondary infections.

Anterior uveitis, retinal disease and blindness have been

reported. Chronically infected dogs may also develop arthritis,

renal failure, interstitial pneumonia or polymyositis.

Reproductive disorders have been reported, including prolonged

bleeding during estrus, inability to conceive, abortion

and neonatal death. Death can occur as a consequence

of hemorrhages or secondary infections.

Neurological signs can be seen either during the acute

or the chronic stage. They may include depression, ataxia,

vestibular dysfunction, generalized or localized hyperesthesia,

intention tremors of the head, paraparesis or tetraparesis,

cranial nerve deficits, seizures, and coma.

[/quote]

I wouldn’t be too concerned about the Ehrlichia test if the dog hasn’t travelled abroad. I believe it is only Anaplasma phagocytophilum (formerly Ehrlichia) that we see in the UK. There are a few reports of the neurological signs seen in dogs that are seropositive to A phagocytophilum. The conclusion is that this is not a common cause of nervous system dysfunction in dogs and if seropositivity is seen then it should not be taken as clear evidence of this disease in dogs.

One interesting study to read on this is a Swedish study looking at seropositivity and the relationship to neurological signs (many more references are given in the paper to previous studies showing similar results):

http://www.ncbi.nlm.nih.gov/pubmed/17575245

Re: ataxic Yorkie

Mark Lowrie — Mon, 20 Aug 2012 10:49:17 GMT

The video does show some stumbling and a degree of ataxia so I would think you are going along the right lines having done a bile acid stim and suspecting inflammatory brain conditions.

How is hopping in all four legs and paw positioning? How is the menace response in each eye? Does the owner mention a change in awareness or mentation in the dog, i.e. is it alert? Has it lost its toilet training behaviour, i.e. urinating or defaecating in the house?

If this is a forebrain disorder, which would certainly fit the history, then you are thinking along the right lines with ruling-out metabolic disease first (bile acid stim – even older YRT can present with congenital portosystemic shunts), and then moving to consider intracranial disease which in a YRT would be inflammatory (necrotising encephalitis or granulomatous meningoencephalitis) and neoplastic as you mentioned.

Moving forward, if the bile acid stim is normal then obviously MRI is best but failing that you can consider CFS – may be a very high risk in this patient though so would be best to perform only after discussing risks with owner. If they don’t want to perform this then treatment with steroids could be considered as inflammatory brain disease would be the only remaining treatable disease but it is always difficult to treat inflammatory brain conditions even when an MRI is performed so very difficult indeed when no MRI is done. I usually start on 1mg/kg pred BID for 4 weeks and then taper the dose by half every 6 weeks thereafter (e.g. 0.5mg/kg BID 6 wks, 0.25mg/kg BID 6 wks, 0.25mg/kg SID for 6 weeks, 0.25mg/kg EOD 6 weeks, 0.25mg/kg every third day 6 weeks – or something along these lines). I also find that without cytarabine things don’t go well so I would try and use this if finances allow (50mg/m2 BID for 4 injections repeated every 3 weeks initially).

In summary, prognosis for most of the conditions is poor except portosystemic shunt and GME. Therefore just treat for the treatable.

Good luck!

Re: ataxic Yorkie

Mark Hedberg — Mon, 20 Aug 2012 09:06:42 GMT

Ehrlichia treatment: 10mg/kg doxycycline once daily and 5mg/kg imidocarb once and only once, good luck! :) (Note: the imidocarb is pretty off-license but does work nicely!)

Re: ataxic Yorkie

James Laidlaw — Mon, 20 Aug 2012 08:35:21 GMT

Is the Ehrlichia test positive something to consider? Could fit the symptoms seen:

(Stolen from IVIS.org)

A wide variety of clinical signs, from mild to severe,

have been reported in the acute stage of E. canis infections.

Some dogs present with nonspecific signs such as fever,

lethargy, anorexia, lymphadenopathy, splenomegaly and

weight loss. Vomiting, diarrhea, lameness, edema in the hind

legs, coughing, dyspnea, and a serous to purulent oculonasal

discharge may also be seen. Symptoms of bleeding disorders

including anemia, mild epistaxis, petechiae and ecchymoses

have been reported. Ocular signs can include anterior uveitis,

corneal opacity, hyphema and tortuous retinal vessels. Focal

chorioretinal lesions, consisting of central pigmented spots

with surrounding areas of hyperreflectivity, may be seen.

Subretinal hemorrhages can cause retinal detachment and

blindness. The acute phase typically lasts for 1 to 4 weeks,

and the symptoms usually resolve spontaneously.

Some dogs that recover clinically from the acute phase

remain subclinically infected for months or years. During

the subclinical stage, an infected dog can clear the parasite,

remain infected but asymptomatic, or develop chronic

disease. There may also be progressive deterioration in the

hematologic values during this stage. The conditions leading

to the development of the chronic phase are unknown.

In the chronic phase, common symptoms include chronic

weight loss, weakness, depression, fever, anorexia, and

edema of the limbs, tail and scrotum. Bleeding disorders

occur frequently, and may result in pale mucous membranes,

petechiae, ecchymoses, epistaxis, hematuria or melena. Pancytopenia

can occur, and may lead to secondary infections.

Anterior uveitis, retinal disease and blindness have been

reported. Chronically infected dogs may also develop arthritis,

renal failure, interstitial pneumonia or polymyositis.

Reproductive disorders have been reported, including prolonged

bleeding during estrus, inability to conceive, abortion

and neonatal death. Death can occur as a consequence

of hemorrhages or secondary infections.

Neurological signs can be seen either during the acute

or the chronic stage. They may include depression, ataxia,

vestibular dysfunction, generalized or localized hyperesthesia,

intention tremors of the head, paraparesis or tetraparesis,

cranial nerve deficits, seizures, and coma.

Re: ataxic Yorkie

Michael Woodhouse — Sun, 19 Aug 2012 23:41:42 GMT

I hate these sorts of cases. I would push for referral if that is an option. If not then I would give steroids and opiates for the pain and rest. I do admit to sometimes speculatively adding in clindamycin for toxo/antibiotic cover.